Energy weapons is a good choice, because you get some really good Energy weapons (the best one, in my opinion, you get right in the beginning). Also Melee weapons are pretty good against one of the hardest enemies in the DLC, which there are quite a few of (a type of scorpion).
But it's a pretty balanced DLC skillwise, and overall.
Runite posted... You don't need melee weapon skill to tear roboscorpions apart with a proton axe. The EMP effect is a fixed 50 damage regardless of skills, so just circlestrafe and flail away.
^ what this guy said.
the Proton Axe and the Protonic Inversal Axe are a must regardless of skill, they save so much ammo and time when facing groups of Roboscorpions.
i have 100 in Guns, Cowboy and use .44 Magnum SWC with a full condition Trail Carbine, yet it still takes a stupid amount of rounds to take down Roboscorpions. i picked up the PA and PIA and they die in a few swings.
chug some chems/food and throw yourself at them whilst circle-strafing and you should be able to destroy them all without losing too much health.
WHAT HAVE YOU DONE TO MY TOPIC???__carwreck__ [REPAIR 85] Helios one cab give peer too if fixed.
In OWB there are a lot of clothing options that will allow you to raise other OWB pertinent stats, such as Medicine, Science and such. I'd bring some Party Time Mentats (Mentats, Whiskey, Honey Mesquite Pod... I think) with you as well, just for good measure.
...And a buttload of Energy Ammo. I dunno, maybe I was doing something wrong my first time through, but toward then end I found I had JUST enough ammo to finish up.
-- The following became a big factor in my playthrough, so it's worth keeping in mind --
Before you depart for OWB, go to a doctor and get a check up. Heal your Rads, Splint any busted limbs, and most importantly: Cure Addictions. If you're not addicted to anything GET addicted to something and then have it cured. The last thing you wanna do is start OWB, drink one beer, and find yourself carrying around an annoying addiction that doesn't leave until you hunt down the key item needed to cure it.
"This game is like picking your ASS and then picking your nose!"
The Auto-Doc clears addictions whenever you use its healing function.
From my (shaky) memory, the requirements for various checks:
100 Science 85 Medicine 75 Guns 50 Energy Weapons 25 Barter, I think? 75 Speech 75 Repair 9 Intelligence
The 9 INT one seems really daunting since it's the only one tied to a SPECIAL stat, but it's trivial to boost your INT by as much as 8 by using both kinds of Mentats and some OWB clothes. Any character can pass it.